Azure AD B2C signin gives server_error

Arne 6 Reputation points
2021-10-01T13:15:17.86+00:00

Some time ago, using the Azure Portal, we created Azure AD B2C tenants and got implicit grant flow working for the B2C_1 signin flow with MSAL Angular.

Today, using the Azure Portal, we created a new tenant with the same options as previously, but signin fails: The following request:

https://[REDACTED].b2clogin.com/[REDACTED].onmicrosoft.com/b2c_1_signin/oauth2/v2.0/authorize?response_type=token&scope=https%3A%2F%2F[REDACTED].onmicrosoft.com%2Fapi%2Fuser_impersonation%20openid%20profile&client_id=419bcab7-064e-4ec6-bafa-9090218c1bfa&redirect_uri=https%3A%2F%2F[REDACTED].westeurope.cloudapp.azure.com&state=[REDACTED]&nonce=b0554c3a-e20f-4fb1-9247-85c44277654d&client_info=1&x-client-SKU=MSAL.JS&x-client-Ver=1.3.4&client-request-id=2bdd6d9a-5e20-4276-8148-52e0acb7e0fa&prompt=none&response_mode=fragment

fails with a redirection to the default URL with

error=server_error&error_description=AADB2C%3a+An+exception+has+occurred.%0d%0aCorrelation+ID%3a+1edfd531-18b6-488f-ae42-122733fa480f%0d%0aTimestamp%3a+2021-10-01+12%3a52%3a48Z%0d%0a&state=[REDACTED]

What has changed?

How do we debug the problem?

Microsoft Entra External ID
Microsoft Entra External ID
A modern identity solution for securing access to customer, citizen and partner-facing apps and services. It is the converged platform of Azure AD External Identities B2B and B2C. Replaces Azure Active Directory External Identities.
2,753 questions
Microsoft Entra ID
Microsoft Entra ID
A Microsoft Entra identity service that provides identity management and access control capabilities. Replaces Azure Active Directory.
20,501 questions
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